The toxicity of cade oil (Juniperus oxycedrus), its constituents and structurally related compounds toward adult house dust mite Dermatophagoides farina was examined. Results were compared with two commercially available acaricides, benzyl benzoate and deet. The cade oil constituents were identified by GC-MS analysis. Citral (LC50, 1.13 μg cm–2) and methyleugenol (LC50, 5.78 μg cm–2) were the most toxic compounds, followed by eugenol (LC50,12.52 μg cm–2), nerol (LC50, 21.4 μg cm–2) and terpinen-4-ol (LC50, 29.55 μg cm–2) were shown significant mortality against adult of D. farina. Toxicity of citral, methyleugenol were higher than that of benzyl benzoate, and above listed compounds was all more toxic than deet. Given the result of vapour-phase mortality tests that these compounds were more toxic in closed containers than in open ones, we concluded that vapour action plays a great role in their mode of delivery. Cade applied as 3 and 4% experimental sprays provided 96 and 100% mortality against the mites respectively, whereas permethrin (cis:trans, 25:75) 2.5 g/l spray treatment resulted in 17% mortality. Cade oil, and its constituents shown their potentials as effective alternatives for harmful synthetic acaricides for the control of Dermatophagoides populations as fumigants in contact and therefore illustrated the need for further study of this essential oil.

• Haribalan Perumalsamy(Research Institute for Agriculture and Life Science, Seoul National University)
• Jun-Ran Kim(Department of Crop Life Safety, National Academy of Agricultural Science)
• Young-Joon Ahn(Department of Agricultural Biotechnology, Seoul National University)